Celebrities, fans and pro tennis players come together at the BNP Paribas Showdown.

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BNP Paribas Showdown

NEW YORK, NY - MARCH 04: Juan del Potro of Argentina returns a shot to Rafael Nadal of Spain during the BNP Paribas Showdown on March 4, 2013 at Madison Square Garden in New York City. (Photo by Elsa/Getty Images)